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Case Report Acute Labyrinthitis Secondary To LABYRINTHITIS SECONDARY TO TICK INFESTATION CASE REPORT ACUTE LABYRINTHITIS SECONDARY TO AURAL TICK INFESTATION Abdul Halim Shibghatullah1, Mohd Khir Abdullah1, Cheong Jack Pein1 and Irfan Mohamad2 1Department of Otorhinolaryngology, Hospital Pakar Sultanah Aminah, Muar, Johor; 2Department of Otorhinolaryngology-Head and Neck Surgery, School of Medical Sciences, Universiti Sains Malaysia, Kota Bharu, Kelantan, Malaysia Abstract. Aural tick usually menisfests as intolerable otalgia. The severity of pain makes the patient to seek early treatment. Other uncommon symptoms include inner ear dyfunctions such as vertigo and tinnitus. The diagnosis is established by clinical examinaion either by otoscopic evidence of the tick itself, or its fecal remnant. We report a case of patient with acute labyrinthitis features with con- curent otoscopic findings of tick fecal material. Keywords: aural, tick infestation, labyrinthitis INTRODUCTION CASE REPORT Aural tick infestation is a common A 69-year-old Malay woman with no phenomenon in tropical countries. It previous medical history presented with is the second most common athropod sudden onset vertigo, tinnitus and pain in foreign body found in human ear canals the right ear for one week. The symptoms (Indhudaran et al, 1999). The most com- worsened until she developed decrease mon presentation is ear pain, which can hearing in the right ear and vomiting sometimes be intolerable. Other reported one day prior to admission. She had no presentations include facial palsy, an preceding symptoms of viral upper re- edematous ear canal and regional lymph- spiratory tract infection. On examination adenopathy (Edussuriya and weilgama, she was alert and had normal vital signs. 2003). However tick infestation causing Otoscopic examination revealed multiple inner ear dysfunction is rare. We report feces of a tick overlying her right tym- here such a case. panic membrane. No live tick was found. There was also noted to have nystagmus Correspondence: Dr Irfan Mohamad, Depart- but no facial nerve palsy. Her left ear ex- ment of Otorhinolaryngology-Head & Neck amination was normal. Surgery, School of Medical Sciences, Universiti Sains Malaysia Health Campus, 16150 Kota Pure tone audiometry showed severe Bharu, Kelantan, Malaysia. to profound right sensorineural hearing Tel: 609 7676420 loss (Fig 1). The tick feces were removed E-mail: [email protected] by suctioning and she was prescribed Vol 43 No. 4 July 2012 857 SOUTHEAST ASIAN J TROP MED PUBLIC HEALTH Frequency in Hertz (Hz) betahistine and methyl- 250 500 1,000 2,000 4,000 8,000 -10 cobalt. Her symptoms improved and she was ) 0 discharge on those medica- 10 tions. Repeated pure tone 20 audiometry one month ANSI, 1996 30 later showed reversal of her symptoms (Fig 2). 40 50 DISCUSSION 60 Ticks can release a 70 toxin from their salivary 80 gland which can cause fa- 90 cial nerve palsy. The toxin 100 can interfere with synthesis or release of acethylcholine 110 from the motor end plate of Hearing level in decibels (dB HL) (RE: 120 the nerve (Vedanaryanan Tympanograms et al, 2004). Fig 1–Right ear pure tone audiometry on presentation showing Acute labyrinthitis is severe to profound sensorineural hearing loss. the most likely cause of vertigo and tinnitus in this Frequency in Hertz (Hz) patient because the dura- 250 500 1,000 2,000 4,000 8,000 tion of symptom was one -10 week. Vestibular neuronitis 0 usually preserves the audi- 10 tory function which was af- fected in this patient. Pure 20 tone audiometry showed ANSI, 1996) 30 reduced hearing which 40 had improved one month 50 later. Since the onset of the symptoms occurred at the 60 same time as the otalgia 70 and the presence of tick 80 fecal matter, we conclude 90 the cause of the acute laby- rinthitis was toxin from an 100 aural tick bite. It is pos- 110 sible there was concomitant Hearing level in decibels (dB HL) (RE: 120 acute viral labyrinthitis but the patient had no other Tympanograms symptoms consistent with Fig 2–Right ear pure tone audiometry one month after treatment. this diagnosis. 858 Vol 43 No. 4 July 2012 LABYRINTHITIS SECONDARY TO TICK INFESTATION Aural tick infestation is diagnosed REFERENCES by either presence of the tick or tick fecal American National Standard Institute (ANSI). material in the auditory canal (Srinovi- S3.6-1996. Specification for audiometers. anti and Raja Ahmak, 2003). Aural ticks New York: American National Standards should be managed the same as other Institute, 1996. foreign bodies in the ear. If the insect is Dalgic A, Kandogan T, Kavak H, Ari A, Erkan still alive at presentation, lidocaine ear N, Ozuer MZ. Ticks in the external audi- drops can be instilled in the ear to reduce tory canal. Hong Kong J Emerg Med 2010; discomfort and chloroform may be used 17: 190-2. to reduce insect motility (Fegan and Glen- Edussuriya BD, Weilgama DJ. Case reports: non, 1996). The tick should be removed intra-aural tick infestations in humans in complete with the mouth parts. The dura- Sri Lanka. Trans R Soc Trop Med Hyg 2003; tion of the attachment is related to the risk 97: 412-3. for transmission of the infectious agents Fegan D, Glennon J. Intra-aural ticks in Nepal. (Dalgic et al, 2010). Lancet 1996; 348: 1313. Aural tick infestation can present Indhudaran R, Ahamad M, Ho TM, Salim R, with otalgia, or may be accompanied Htun YN. Human otoacariasis. Ann Trop by other symptoms, such as vertigo and Med Parasitol 1999; 93: 163-7. hearing loss, due to the tick toxin. A high Srinovianti N, Raja Ahmad RLA. Intra-aural degree of clinical suspicion is important, tick infestation: The presentation and com- especially when the insect is no longer plications. Intern Med J 2003; 2: 21. present. Treatment should be carried out Vedanarayanan V, Sorey WH, Subramony in a timely manner to reduce risk of other SH. Tick paralysis. Semin Neurol 2004; 24: complications. 181-4. Vol 43 No. 4 July 2012 859.
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